Brake band



My 22, 1930. H. BORCHERS 1,171,204

' 'BRAKE BAND Fiied May 22, 1925 Y Patented July 22, 1930 UNITED STATES PATENT. OFFICE HEINRICH BOB/CHEERS, OF NIENIBURG-ON- WESER, GERMANY, ASSIGNOR 01' AN UN- DIVIDED PART TO RUDOLF ALDAG, OI NIENBURG-ON-WESER, GERMANY BRAKE BAND Application filed May 22, 1925, Serial No. 32,108, and in Germany May 28, 1924.

This invention has reference to improvements in brakes formotor vehicles and for other purposes, and it refers in particular to a novel method of increasing the efliciency 5 of brake bands or brake coverings, facings or i the like by providing a more thoroughly engaging frictional braking surface. than it was possible to obtain in the devices heretofore :in use. According to the prior art, such 1 braking covering Whigh =were employed as a stufiing for the brake jaws for motor vehicles and the like have usually been manufactured as hard, rather rigidly woven bands of asbestos with metal insertions. These insertion pieces usually consisted of wire insertions so arranged as to be enclosed by the individual asbestos threads, and in pursuance thereof such inserts could not produce by themselves any. increase of the braking action.

In view thereof my invention is intended to devise means of so manufacturing and arranging braking bands as to increase the frictional contact of the same, which, in the practice of my invention, may be effected in a preferred embodiment by. incorporating I small-sized roughening agents, such as finely sifted sand, grit, iron filings and the like with the several weaving threads in the manufacture of textile fabrics or before working the threads into fabrics or by causing such agents to adhere to the individual threads. This union of the roughening agents with the textile fabric is carried out preferably by introducing the grit-like roughening agents during the Weaving process of the textile fabric at a point near the weave crossing of the warp threads of the fabric formin the brake-band. According to a preferre embodiment of the invention the threads .are in a moist condition, and the granular frictional substances, as for instance finely sifted sand or iron filings, disintegrated shavings of cast iron or the like are introduced by showering, strewing, blowing or by injection, and the said roughening agents, sand or the like, may be mixed, moreover, with an adhesive, so as to increase their sticking properties.

With a view of aiding in the clear undergrammatically on the accompanying drawing by way of example the mode of operation of the invention in two different relative positions of the threads and of the lay or batten, Figure 1 showing the weft or filling thread on the open shed and Figure 2 illustrafting the beating up of the newly inserted we t.

In the drawings :d is the reed, f the lay or batten, 0 and 0 indicate the warp threads, his the weft or filler, 12 indicates the new, freshly inserted-weft, a indicates roughly the grit or sand introduced at the weave points.

The roughening agents are applied in accordance with the invention at the .weave points or the points of intersection of the warp threads 0, 0 while the shed is open and the weft, as appears from the drawing, is run in at a distance from said roughening agent a, so that the latter a is situated between said point of intersection or union of the warps c c and the weft b, b. The insertion of the grit or roughening agent in one form of embodiment of the invention may be effected by projecting it at an inclination against such point of union, but it may also be showered onto said point in any usual or approved manner. After the grit has been introduced and the weft has been run in, the reed is caused to beat up the weft in the ordinary -manner, as shown in Fig. 2 of the drawing, the warps are changed, the lay returns and the shed is opened and the cycle of operations is continued.

Inasmuch as the shed forming threads 0, 0' are kept .at rest in the open position of the shed, and the weft 6, before beating up, is situated at quite a distance from the point of intersection of the warps c, 0', the weft may be run in without being in the least interferedwith by the grit or roughening agent a which is substantially retained at said point of intersection by the moisture of the threads. When the reed d is beating up the weft thread 6, the reed is protected by said weft from contactwith the grit interposed between the weft and the point of intersection of the warps c, and the grit is thereby also practically kept away from the shuttle race of the lay or batten; and even,

provided any inappreciable, slight amounts of grit should happen to get on the shuttle race, they may be easily swept away and removed by the operator. Nor is there any possibility of the heddles or eyes through which the warp threads are made to pass in the usual, well-known manner and which are situated behind the reed, as seen from the stand-point of the operator being affected by the treatment with the roughening material, inasmuch as said material is introduced at a considerable distance from such heddles, and, if, as aforesaid, the introduction of said grit or roughening material takes place at an inclination to the horizontal, the grit may be blown away from the reed and the heddles.

The drying of the finished, band-like fabric may be slowly effected at the open air. By drying the product, however, at a high temperature, that is to say by rapid drying, a greater resistency against water and oil will be obtained. This is due to the fact that by the rapid drying a kind of baking action is produced which causes the pores of the fabric to be thoroughly closed and all remnants of moisture to be removed from the surface, so as to result in a comparatively hard, indurated protective combination of outer layers,while, when the drying is slowly effected and at a lower temperature, a more porous, somewhat spongy material is obtained which is less resisting to the influences of water and oil. After the drying operation the sheet or band may be submitted to a pressing operation for the purpose of thoroughly forcing-in and incorporating the grit or roughening agent with the material of the fabric, and the product may then be smoothened in the usual way by calender rollers and the like.

The woven fabric obtained according to this invention retains the grit, sand or other roughening material morethoroughly than it is possible to produce by merely impressing and forcing such roughening agents into textile or similar material, and it is thoroughly charged throughout with the roughening agents, as appears by cutting such fabric according to my invention to pieces. A highly superior braking action may thus be obtained, even in case the product according to this invention is applied to braking jaws and discs which have been very heavily soiled with oil, so as to vouchsafe the highest degree of safety of operation of the braking instrumentalities under all condition of motor-riding and the like, as has been shown by a great variety of practical tests made with the braking material according to this invention.

Any impregnating adhesive used should be as proof and unaffected as possible against water and oil or fat, as well as against the action of heat.

The principle underlying the invention is not restricted to the particular mode of operation and instrumentality herein shown and described by way of exemplification, and it should be understood that the manner of incorporating the roughening agents with the textile material may be modified, and different kinds of roughening agents others than those hereinbefore referred to may be used and within the scope and spirit of my invention as particularly set forth and defined in the claims hereunto appended.

I claim 1. The method of manufacturing brake bands, which consists in weaving moist asbestos fibers and the like into a textile fabric and introducing grit-like roughening agents during the weaving operation near the weave crossing of the moist threads.

2. The method of manufacturing brake bands, which consists in weaving moist asbestos threads and the like into a fabric, and during the Weaving sprinkling grit-like comminuted roughening agents between the moist shed forming threads near the crossings thereof.

3. The method of manufacturing brake bands, which consists in incorporating gritlike roughening agents with a moist asbestos fabric and the like, and drying the resulting product by heat into a relatively hard, highly resisting body, and thereby increasing the resistency against water and oil.

4. The method of manufacturing brake bands, which consists in weaving moist asbestos threads and the like into a textile fabric, blowing and injecting grit-like roughening material between the moist shed-forming threads at the-point of intersection thereof during the weaving process, then highly heating and finishing the fabric and incorporating the roughening material therewith.

HEINRICH BORCHERS. 

